One of those little extras that travelers often overlook when budgeting for a trip is the cost of airport parking. And if you live in a major metropolitan area, and you park at the airport, this is one little extra that's not so little.

The Top Eleven

Forbes.com has compiled a list of the eleven US airports where on-site parking is most expensive. Topping the list is Chicago - O'Hare where it can cost a whopping $50 a day to park at the airport.

If you reserve parking through GoNOMAD at an off-site lot right near O'Hare, it will cost you $10 per day or less.

The cost of parking at the airport is often many times the cost of the off-site parking lots you can access through our Airport Parking page. Not only that, you eliminate the risk of arriving at the airport to find all the lots are full.

You pay the cost of one day's parking in advance, and that's is taken off your bill when you pick up your car. Your space is guaranteed, and you avoid waiting in traffic when airport security personnel are checking incoming vehicles.

At Los Angeles, for example, prices at off-site lots ranged from $5.95 to $11 per day, compared with $30 for airport lots. You can park off-site in Newark for as little as $9 a day, compared with $24 at the airport.

Off-site parking in Denver costs $4.99 to $7.99 per day, compared with $18 at the airport.

"A Significant Premium"

Forbes based its list on a study conducted by Miami International Airport of other airports with similar passenger volume and similar ratios of international to domestic travelers, to determine how much they ought to raise their rates. MIA wound up increasing rates by 25 percent, but even then they didn't make the top eleven list.

Forbes writer Sophia Banay says increases in on-site airport parking are due to a variety of factors, including rising energy costs, garage construction costs and the cost of bussing operations, but she adds that parking is an important source of revenue for the airports, and when demand is high they often charge "a significant premium."

What the Market Will Bear, and Then Some

Banay quotes Pat Gleason of the Center for Airport Management: "Some airport parking rates are determined by contract. At other airports, the average parking rate has to equal or exceed that of competitive airports around a specific formula. And some airport parking pricing is driven by the market. The greater the demand for on-airport parking, the higher the rate."

In other words, airports are probably going to charge as much as the market can bear and maybe a little more on top of that.

Eliminating Hassles

Besides being a lot less expensive, reserving a space at an off-site lot also eliminates many of the hassles that result from ever-increasing airport security measures. Since you leave your car outside the airport, it isn't subject to searches and sceenings. This can save you a lot of time waiting in traffic, especially at times when security is heightened due to some kind of alert.

Off-site lots are safe and secure, and they provide reliable transportation to departure terminals 24 hours a day. Many offer valet service (at an additional charge) and many are covered.

All in all off-site airport parking represents an alternative that is more reliable, involves fewer hassles and is much, much cheaper than parking at the airport.

Another option many travelers are choosing is to "Park, Sleep and Fly," reserving a hotel room for the night they leave or the night they return, or both. If you live fairly far away from the airport this will make your trip a lot less frazzled and more leisurely and relaxing.

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